Bicycle frame



FIG. 1 is a right-rear perspective view of the design for the bicycle frame;

FIG. 2 is a left-front perspective view thereof;

FIG. 3 is a right view thereof;

FIG. 4 is a left view thereof;

FIG. 5 is a front view thereof;

FIG. 6 is a rear view thereof;

FIG. 7 is a top view thereof; and,

FIG. 8 is a bottom view thereof.

The broken lines immediately adjacent the solid lines define the boundaries of the claimed design while all other broken lines depict the environment and are for illustrative purposes only; the broken lines form no part of the claimed design. 

CLAIM The ornamental design for a bicycle frame, substantially as shown and described. 